Anti-surge volute structure and turbine fluid machine applying same

Abstract

The invention discloses an anti-surge volute structure and a turbine fluid machine applying the anti-surge volute structure. A middle ejection plate is provided with a left drainage face, a right drainage face, a middle ejection flow path and an ejection plate outflow end. The inner side walls of the left-side inflow ring section and the right-side inflow ring section form a concave-convex wave-shaped structure along the ring sections; the middle injection flow path penetrates through the left-side flow inlet volute, the right-side flow inlet volute and the middle injection plate; a flow path structure which is gradually shrunk in the outflow direction is formed between the left outflow section and the left drainage surface, and a flow path structure which is gradually shrunk in the outflow direction is formed between the right outflow section and the right drainage surface; an outlet of the middle ejection flow path is located at the front edge of the blade close to the hub side. As the volute structure and the turbine fluid machinery applying the volute structure are improved, the problems of low adaptability, large flow loss, poor variable working condition performance, low efficiency, high surge and the like are solved, and the working condition performance and the operation efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid machinery, in particular to an anti-surge volute structure, and more particularly to a turbine fluid machinery using the same. Background Art

[0002] Compressors, pumps, fans, turbines, etc. are all common working parts in the field of fluid machinery, which are of great significance to production and life. For example, centrifugal compressors can usually make the gas obtain a higher pressure. Centrifugal compressors are usually blade-type rotating machinery. The working mode of centrifugal compressors is usually that after the gas enters the impeller of the centrifugal compressor, under the action of the impeller blades, it rotates at high speed with the impeller, and flows to the impeller outlet under the action of the rotating centrifugal force, and is subjected to the expansion effect of the impeller, so that the pressure energy and kinetic energy of the gas are increased. Subsequently, in the expansion flow channel, this part of the kinetic energy is converted into static pressure energy, thereby further increasing the gas pressure. The turbine converts the high-enthalpy airflow from the upstream into a low-enthalpy airflow, converts the internal energy of the gas into kinetic energy, and thus drives the impeller's rotating shaft to output the kinetic energy into mechanical energy. Its main flow components include volute, nozzle, impeller and diffuser. After the high-temperature and high-pressure airflow enters the volute, it flows into the nozzle, impeller and diffuser, and finally the low-temperature and low-pressure airflow leaves the turbine and outputs work.

[0003] The fundamental reason for fluid machinery surge is that the airflow field produces local distortion at low flow rates, that is, when the flow rate is too small, the airflow first changes pressure at the impeller outlet and produces an airflow disturbance at the outlet. The airflow disturbance propagates along the impeller hub line to the impeller inlet. When it reaches the leading edge of the main blade, it is converted into circumferential distortion of the airflow outside the impeller inlet. This circumferential distortion is the surge phenomenon. The volute is a commonly used flow component in compressors, pumps, fans, and turbine machinery. The arrangement of its structure directly affects the frequency of surge. By designing the volute structure, the safe operation of the unit can be guaranteed and the unit's operating efficiency can be improved. It can be seen that it is very necessary to optimize the design of the volute.

[0004] Prior art CN201582209U discloses an anti-surge structure of a turbocharger compressor volute, which includes a compressor volute 1, a plurality of circular holes 11 are opened on the inner wall of the compressor volute 1, the direction of the circular holes 11 is basically consistent with the inlet air flow direction in the compressor volute 1 when the turbocharger is working, and the plurality of circular holes 11 are evenly arranged on the inner wall of the compressor volute 1 in a circumference, and an annular groove 13 is provided on the inner wall of the compressor volute 1 at the tail of the plurality of circular holes 11, which connects the plurality of circular holes 11 with the air inlet 12 of the compressor volute 1. The plurality of circular holes 11 and the annular groove 13 widen the flow of the compressor and avoid the occurrence of surge and blockage of the supercharger.

[0005] However, the above-mentioned volute has design limitations, and only involves the design of some non-universal volute structures, and does not fundamentally change the volute structure. It has poor adaptability, large flow losses, poor variable operating performance, low efficiency, and high surge. Therefore, in response to these problems, the applicant proposes an anti-surge volute structure and a turbine fluid machinery using the same to solve the above-mentioned problems and improve operating performance and efficiency. Summary of the invention

[0006] The purpose of the present invention is to solve the shortcomings of the prior art and to propose an anti-surge volute structure and a turbine fluid machinery using the same.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A surge prevention volute structure, comprising a shaft, a hub, blades, and a volute; the blades are mounted on the hub to form an impeller, and the shaft passes through the volute and is connected to the hub; the characteristics are: the volute is composed of a left inlet volute, a right inlet volute, an intermediate ejector plate, and an outlet housing; the left inlet volute and the right inlet volute are located on both sides of the intermediate ejector plate; the left inlet volute comprises a left inlet ring section, a left outlet section, and a left inlet portion, and the right inlet volute comprises a right inlet ring section, a right outlet section, and a right inlet portion; the intermediate ejector plate has There are a left-side guide surface, a right-side guide surface, a middle guide flow path, and an outlet end of an guide plate; the inner side walls of the left-side inlet ring section and the right-side inlet ring section form a concave and convex wave structure along the ring section; the middle guide flow path runs through the left-side inlet volute, the right-side inlet volute and the middle guide plate; a flow path structure that gradually shrinks along the outlet direction is formed between the left-side outlet section and the left-side guide surface, and a flow path structure that gradually shrinks along the outlet direction is formed between the right-side outlet section and the right-side guide surface; the outlet of the middle guide flow path is located at a position where the leading edge of the blade is close to the hub side.

[0009] Furthermore, in the radial cross-sectional projection of the volute structure, a curve formed by unfolding the waveform structure along a straight line on a plane is a sine function or a cosine function.

[0010] Furthermore, the curve formed by the expansion of the waveform structure in the left inlet volute is a sine function, and the curve formed by the expansion of the waveform structure in the right inlet volute is a cosine function.

[0011] Furthermore, there is an angle between the flow direction of the left inlet portion and the flow direction of the right inlet portion.

[0012] Furthermore, the angle is between 30° and 60°.

[0013] Furthermore, the left outflow section and the left guide surface form a tapered fluid channel in the flow direction, the axial inlet width of the left inlet is L1, and the axial outlet width of the left outlet is W1, wherein 0.3L1<W1≤0.5L1.

[0014] Furthermore, the right outflow section and the right guide surface form a tapered fluid channel in the flow direction, the axial inlet width of the right inlet is L2, and the axial outlet width of the right outlet is W2, wherein 0.5L2≤W2<0.8L2.

[0015] Furthermore, the axial inlet width L1 of the left inlet and the axial inlet width L2 of the right inlet have the following relationship: L1≤L2.

[0016] Furthermore, the axial outlet width W1 of the left outlet and the axial outlet width W2 of the right outlet have the following relationship: W1 ≥ W2.

[0017] Furthermore, the axial cross-section of the middle injection flow path is an elliptical structure.

[0018] Furthermore, the radial cross section of the outflow end of the ejector plate is in a semicircular, triangular or truncated cone structure.

[0019] A turbine fluid machinery, characterized in that it comprises the above-mentioned anti-surge volute structure.

[0020] The invention discloses an anti-surge volute structure and a turbine fluid machinery using the same, which comprises a shaft, a hub, blades and a volute; the blades are mounted on the hub to form an impeller, and the shaft passes through the volute and is connected to the hub; the characteristics are as follows: the volute is composed of a left inlet volute, a right inlet volute, an intermediate ejector plate and an outlet housing; the left inlet volute and the right inlet volute are located on both sides of the intermediate ejector plate; the left inlet volute comprises a left inlet ring section, a left outlet section and a left inlet portion, and the right inlet volute comprises a right inlet ring section, a right outlet section and a right inlet The middle ejector plate has a left drainage surface, a right drainage surface, a middle ejector flow path, and an ejector plate outlet end; the inner wall of the left inlet ring section and the right inlet ring section forms a wavy structure along the ring section; the middle ejector flow path runs through the left inlet volute, the right inlet volute and the middle ejector plate; a flow path structure that gradually shrinks along the outflow direction is formed between the left outflow section and the left drainage surface, and a flow path structure that gradually shrinks along the outflow direction is formed between the right outflow section and the right drainage surface; the outlet of the middle ejector flow path is located at the position of the leading edge of the blade close to the hub side. Due to the improvement of the volute structure and the turbine fluid machinery using it, the problems of poor adaptability, large flow loss, poor variable operating performance, low efficiency, high surge, etc. are solved, and the operating performance and operation efficiency are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a structural schematic diagram of a volute in the prior art;

[0022] Figure 2 It is a schematic diagram of the axial section of the volute structure;

[0023] Figure 3 It is an enlarged schematic diagram of the axial section of the volute structure;

[0024] Figure 4 It is a schematic diagram of the structure of the wave structure unfolded along a straight line on a plane.

[0025] In the figure: shaft 1, hub 2, blades 3, volute 4, left inlet volute 41, left inlet ring section 411, left outlet section 412, left inlet portion 413, right inlet volute 42, right inlet ring section 421, right outlet section 422, right inlet portion 423, middle ejector plate 43, left guide surface 431, right guide surface 432, middle ejector flow path 433, ejector plate outlet end portion 434, outlet shell 44, corrugated structure 5, axial inlet width L1 of left inlet 414, axial outlet width W1 of left outlet, axial inlet width L2 of right inlet 424, axial outlet width W2 of right outlet 425. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0028] like Figure 1-4As shown, an anti-surge volute structure includes a shaft 1, a hub 2, blades 3, and a volute 4; the blades 3 are installed on the hub 2 to form an impeller, and the shaft 1 passes through the volute 4 and is connected to the hub 2; it is characterized in that: the volute 4 is composed of a left-side inlet volute 41, a right-side inlet volute 42, an intermediate ejector plate 43, and an outlet shell 44; the left-side inlet volute 41 and the right-side inlet volute 42 are located on both sides of the intermediate ejector plate 43; the left-side inlet volute 41 includes a left-side inlet ring section 411, a left-side outflow section 412, and a left-side inlet portion 413, and the right-side inlet volute 42 includes a right-side inlet ring section 421, a right-side outflow section 422, and a right-side inlet portion 423; the intermediate ejector plate 43 has a left guide surface 431, a right guide surface 432, a middle guide flow path 433, and an outlet end portion 434 of the guide plate; the inner side walls of the left inlet ring segment 411 and the right inlet ring segment 421 form a concave and convex wave structure 5 along the ring segment; the middle guide flow path 433 runs through the left inlet volute 41, the right inlet volute 42 and the middle guide plate 43; a flow path structure that gradually contracts along the outlet direction is formed between the left outlet segment 412 and the left guide surface 431, and a flow path structure that gradually contracts along the outlet direction is formed between the right outlet segment 422 and the right guide surface 432; the outlet of the middle guide flow path 433 is located at a position where the leading edge of the blade 3 is close to the hub 2.

[0029] The shape and structure of the volute significantly affect the aerodynamic efficiency of the air. The fluid enters the volute through the left inlet 413 and the right inlet 423. The geometric characteristics of the volute will cause the distribution of the relative velocity of the fluid, which will affect the distribution of the flow state along the wall and ultimately affect the loss and efficiency caused by vibration. The volute in this application is different from the conventional volute in the prior art. After research, the applicant found that the quality of the flow wall structure design of the volute directly affects the intensity of surge. In response to the above problems, the applicant optimized the flow wall structure of the volute and adopted a double volute inlet flow. The double volute can be a symmetrical structure. It can also be an asymmetric structure, and can be combined with an intermediate ejector plate 43 for jet drainage. This type of jet drainage accelerates the movement of the fluid, reduces the residence time of the fluid in the volute, and reduces the impact of surge. In addition, the inner wall of the left inlet ring segment 411 and the right inlet ring segment 421 forms an undulating wave-shaped structure along the ring segment, which also makes the contact area of ​​the fluid in the cavity larger, reduces the possibility of concentrated surge occurring in a certain place, and reduces the impact of surge. The tapered flow path structure combined with the intermediate ejector flow path 433 is more conducive to accelerating the fluid flow and reducing the impact of surge.

[0030] Furthermore, in the radial cross-sectional projection of the volute structure, a curve formed by unfolding the wave-shaped structure 5 along a straight line on a plane is a sine function or a cosine function.

[0031] Furthermore, the curve formed by the expansion of the wave structure 5 in the left inlet volute 41 is a sine function, and the curve formed by the expansion of the wave structure 5 in the right inlet volute 42 is a cosine function.

[0032] The waveform surface of the sine function or cosine function plays a vital role in improving the flow state, which can help reduce vibration and stabilize the fluid flow state.

[0033] Furthermore, there is an angle between the inlet direction of the left inlet portion 413 and the inlet direction of the right inlet portion 423 .

[0034] Furthermore, the angle is between 30° and 60°.

[0035] The left inlet portion 413 and the right inlet portion 423 complement each other in terms of inflow, and their structural arrangement enables the fluids to complement each other when entering the impeller, thereby improving the circulation efficiency and reducing the possibility of surge.

[0036] Furthermore, the left outflow section 412 and the left guide surface 431 form a tapered fluid channel in the flow direction, the axial inlet width of the left inlet 414 is L1, and the axial outlet width of the left outlet 415 is W1, wherein 0.3L1<W1≤0.5L1.

[0037] Furthermore, the right outflow section 422 and the right guide surface 432 form a tapered fluid channel in the flow direction, the axial inlet width of the right inlet 424 is L2, and the axial outlet width of the right outlet 425 is W2, wherein 0.5L2≤W2<0.8L2.

[0038] Furthermore, the axial inlet width L1 of the left inlet 414 and the axial inlet width L2 of the right inlet 424 have the following relationship: L1≤L2.

[0039] Furthermore, the axial outlet width W1 of the left outlet 415 and the axial outlet width W2 of the right outlet 425 have the following relationship: W1 ≥ W2.

[0040] Furthermore, the axial cross-section of the middle injection flow path 433 is an elliptical structure.

[0041] Furthermore, the radial cross-section of the outflow end portion 434 of the ejector plate is in a semicircular, triangular or truncated cone structure.

[0042] A turbine fluid machinery, characterized in that it comprises the above-mentioned anti-surge volute structure.

[0043] The invention discloses an anti-surge volute structure and a turbine fluid machinery using the same, which comprises a shaft, a hub, blades and a volute; the blades are mounted on the hub to form an impeller, and the shaft passes through the volute and is connected to the hub; the characteristics are as follows: the volute is composed of a left inlet volute, a right inlet volute, an intermediate ejector plate and an outlet housing; the left inlet volute and the right inlet volute are located on both sides of the intermediate ejector plate; the left inlet volute comprises a left inlet ring section, a left outlet section and a left inlet portion, and the right inlet volute comprises a right inlet ring section, a right outlet section and a right inlet The middle ejector plate has a left drainage surface, a right drainage surface, a middle ejector flow path, and an ejector plate outlet end; the inner wall of the left inlet ring section and the right inlet ring section forms a wavy structure along the ring section; the middle ejector flow path runs through the left inlet volute, the right inlet volute and the middle ejector plate; a flow path structure that gradually shrinks along the outflow direction is formed between the left outflow section and the left drainage surface, and a flow path structure that gradually shrinks along the outflow direction is formed between the right outflow section and the right drainage surface; the outlet of the middle ejector flow path is located at the position of the leading edge of the blade close to the hub side. Due to the improvement of the volute structure and the turbine fluid machinery using it, the problems of poor adaptability, large flow loss, poor variable operating performance, low efficiency, high surge, etc. are solved, and the operating performance and operation efficiency are improved.

Claims

1. An anti-surge volute structure, comprising a shaft (1), a hub (2), blades (3), and a volute (4); the blades (3) are mounted on the hub (2) to form an impeller, and the shaft (1) passes through the volute (4) and is connected to the hub (2); characterized in that: The volute (4) is composed of a left-side inlet volute (41), a right-side inlet volute (42), an intermediate ejector plate (43), and an outlet housing (44); the left-side inlet volute (41) and the right-side inlet volute (42) are located on both sides of the intermediate ejector plate (43); the left-side inlet volute (41) includes a left-side inlet ring section (411), a left-side outlet section (412), and a left-side inlet portion (413); the right-side inlet volute (42) includes a right-side inlet ring section (421), a right-side outlet section (422), and a right-side inlet portion (423); the intermediate ejector plate (43) has a left-side inlet surface (431), a right-side inlet surface (432), an intermediate ejector flow path (413), and a right-side inlet portion (414). 33), an ejector plate outflow end (434); the inner side walls of the left inflow ring section (411) and the right inflow ring section (421) form a concave and convex wave structure (5) along the ring sections; the middle ejector flow path (433) runs through the left inflow volute (41), the right inflow volute (42) and the middle ejector plate (43); a flow path structure that gradually contracts along the outflow direction is formed between the left outflow section (412) and the left flow guide surface (431), and a flow path structure that gradually contracts along the outflow direction is formed between the right outflow section (422) and the right flow guide surface (432); the outlet of the middle ejector flow path (433) is located at a position on the leading edge of the blade (3) close to the hub (2).

2. The anti-surge volute structure according to claim 1, characterized in that: In the radial cross-sectional projection of the volute structure, the curve formed by the wave-shaped structure (5) unfolding along a straight line on a plane is a sine function or a cosine function.

3. The anti-surge volute structure according to claim 2, characterized in that: The curve formed by unfolding the waveform structure (5) in the left inlet volute (41) is a sine function, and the curve formed by unfolding the waveform structure (5) in the right inlet volute (42) is a cosine function.

4. The anti-surge volute structure according to claim 1, characterized in that: There is an angle between the inlet direction of the left inlet portion (413) and the inlet direction of the right inlet portion (423).

5. The anti-surge volute structure according to claim 4, characterized in that: The size of the angle is 30°~60°.

6. The anti-surge volute structure according to claim 1, characterized in that: The left outflow section (412) and the left guide surface (431) form a gradually contracting fluid channel in the flow direction, the axial inlet width of the left inlet (414) is L1, and the axial outlet width of the left outlet (415) is W1, wherein 0.3L1<W1≤0.5L1.

7. The anti-surge volute structure according to claim 6, characterized in that: The right outflow section (422) and the right guide surface (432) form a gradually contracting fluid channel in the flow direction, the axial inlet width of the right inlet (424) is L2, and the axial outlet width of the right outlet (425) is W2, wherein 0.5L2≤W2<0.8L2.

8. The anti-surge volute structure according to claim 7, characterized in that: The axial inlet width L1 of the left inlet (414) and the axial inlet width L2 of the right inlet (424) have the following relationship: L1≤L2.

9. The anti-surge volute structure according to claim 7, characterized in that: The axial outlet width W1 of the left outlet (415) and the axial outlet width W2 of the right outlet (425) have the following relationship: W1≥W2.

10. The anti-surge volute structure according to claim 1, characterized in that: The axial cross section of the middle injection flow path (433) is an elliptical structure.

11. The anti-surge volute structure according to claim 1, characterized in that: The radial cross section of the outflow end portion (434) of the ejector plate is in a semicircular, triangular or truncated cone structure.

12. A turbo fluid machine, characterized in that: The turbine fluid machinery comprises the anti-surge volute structure according to any one of claims 1 to 11.

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